debian+phosh running on PinePhone

[dukla2000]

2.
Under "Language & Region", I can select a UK keyboard layout, but the only entries in "Language" and "Formats" refer to the United States, they cannot be changed.

At a terminal prompt
sudo dpkg-reconfigure locales
then select 140
and 3
(at least those are the options I choose for me in the UK) then you will be able to choose English (UK) for language and United Kingdom formats.
One of my desktop applications, either gnucash or gramps, need the UTF set so I figure it is some kind of lowest denominator and I use it everywhere.